EXPH 386 - Exam 3 (Skeletal Muscle)
Neuromuscular system - Answer-The coordination and integration of the muscles together with the
nerves that supply them
Soma - Answer-Cell body; dictates the critical firing rate of the action potential
Higher - Answer-Larger cell bodies (somas) are associated with _________ critical firing rates.
Dendrites - Answer-Short neural branches that receive impulses through numerous connections and
conduct them toward the body
Axon - Answer-Extends from the cell body in order to deliver action potentials toward the
neuromuscular junction; wrapped by myelin
Myelin sheath - Answer-Lipoprotein membrane that surrounds most of an axon, insulating it and
allowing the transmittance of faster conduction velocities
Larger - Answer-_________ axons are associated with faster conduction velocities
, Schwann cells - Answer-Specialized cells that deposit myelin around the axon
Node of Ranvier - Answer-interruptions in the myelin sheath of axons occurring every 1-2 mm; allows
for the action potential to jump from node to node, speeding conduction
Saltatory conduction - Answer-Rapid transmission of a nerve impulse along an axon, resulting from the
action potential jumping from one node of Ranvier to another, skipping the myelin-sheathed regions of
membrane.
Motor endplate - Answer-Interface between the end of the axon at the terminal branch and the muscle
fiber (neuromuscular junction)
Muscle fiber - Answer-Multinucleated cylindrical cells with force directed long its long axis
30 cm - Answer-Length of the sartorius
endomysium - Answer-Layer of connective tissue that wraps each muscle fiber, separating it from other
fibers
Perimysium - Answer-Surrounds a bundle of up to 150 fibers
Fasciculus - Answer-a large bundle of fibers
Epimysium - Answer-A fascia of fibrous connective tissue that surrounds the entire muscle (outermost
layer)
Sarcolemma - Answer-The muscle fiber membrane residing BENEATH the endomysium. Known as the
TRUE fiber boundary.
Neuromuscular system - Answer-The coordination and integration of the muscles together with the
nerves that supply them
Soma - Answer-Cell body; dictates the critical firing rate of the action potential
Higher - Answer-Larger cell bodies (somas) are associated with _________ critical firing rates.
Dendrites - Answer-Short neural branches that receive impulses through numerous connections and
conduct them toward the body
Axon - Answer-Extends from the cell body in order to deliver action potentials toward the
neuromuscular junction; wrapped by myelin
Myelin sheath - Answer-Lipoprotein membrane that surrounds most of an axon, insulating it and
allowing the transmittance of faster conduction velocities
Larger - Answer-_________ axons are associated with faster conduction velocities
, Schwann cells - Answer-Specialized cells that deposit myelin around the axon
Node of Ranvier - Answer-interruptions in the myelin sheath of axons occurring every 1-2 mm; allows
for the action potential to jump from node to node, speeding conduction
Saltatory conduction - Answer-Rapid transmission of a nerve impulse along an axon, resulting from the
action potential jumping from one node of Ranvier to another, skipping the myelin-sheathed regions of
membrane.
Motor endplate - Answer-Interface between the end of the axon at the terminal branch and the muscle
fiber (neuromuscular junction)
Muscle fiber - Answer-Multinucleated cylindrical cells with force directed long its long axis
30 cm - Answer-Length of the sartorius
endomysium - Answer-Layer of connective tissue that wraps each muscle fiber, separating it from other
fibers
Perimysium - Answer-Surrounds a bundle of up to 150 fibers
Fasciculus - Answer-a large bundle of fibers
Epimysium - Answer-A fascia of fibrous connective tissue that surrounds the entire muscle (outermost
layer)
Sarcolemma - Answer-The muscle fiber membrane residing BENEATH the endomysium. Known as the
TRUE fiber boundary.
